Case IH 2236 (6158.05) - DEC – DEC: Synchro 7 Solenoid - open circuit

The fault code indicates an 'open circuit' on the circuit controlling the Synchro 7 Solenoid, meaning there is a physical break in the electrical path preventing current from flowing. Because the circuit is open, the solenoid cannot energize to direct hydraulic fluid, which will likely result in erratic shifting, late shifting, or a complete loss of the specific transmission gear/synchronizer function.

• MAXXUM T4E
• Maxxum
• Puma
• Magnum
• Optum

1. 1

   Inspect the wiring harness leading to the Synchro 7 Solenoid for visible damage, chafing, or disconnected plugs

2. 2

   Disconnect the solenoid and check the pins for corrosion, moisture, or pushed-out terminals

3. 3

   Use a digital multimeter to check the supply voltage from the DEC to the solenoid harness

4. 4

   Measure the resistance (Ohms) across the pins of the Synchro 7 Solenoid itself. If the multimeter reads 'OL' (infinite resistance), the internal coil is broken (open circuit) and the solenoid is definitively dead

1. 1

   Preparation

   Clean the area around the transmission valve block to prevent contaminants from entering the hydraulic system.

2. 2

   Removal

   Disconnect the electrical cable from the faulty Synchro 7 Solenoid.

3. 3

   Extraction

   Remove the retaining bolts or clips holding the solenoid in place. Carefully extract the solenoid valve from the manifold. (Note: Have a catch pan ready, as some hydraulic fluid will drain).

4. 4

   Installation

   Lubricate the O-rings on the new solenoid with clean hydraulic fluid. Insert the new solenoid into the valve block and secure it with the retaining hardware.

5. 5

   Reconnection

   Reconnect the electrical harness, ensuring it clicks securely into place.

6. 6

   Clear Codes

   Use a diagnostic scan tool or DTC eraser to clear the stored 2236 (6158.05) fault code from the DEC. Run the machine and verify that the transmission shifts correctly.